WASHINGTON — The Supreme Court on Monday ruled that Donald Trump has immunity for some of his conduct as president in his federal election interference case, but maybe not for other actions, adding another obstacle to a trial taking place.

In a novel and potentially consequential case on the limits of presidential power, the justices voted 6-3 along ideological lines to reject Trump’s broad claim of immunity, meaning the charges relating to his attempts to overturn the 2020 election results will not be dismissed, but said some actions closely related to his core duties as president are off-limits to prosecutors.

Chief Justice John Roberts, writing for the majority, said that further proceedings are needed in lower courts to determine what conduct he can be prosecuted for. Among the conduct that the court determined to be core presidential powers and therefore subject to immunity are Trump’s contacts with Justice Department officials and with Vice President Mike Pence in the weeks leading up to the Jan. 6 attack on the Capitol by his supporters.

“The president is not above the law,” Roberts wrote. “But Congress may not criminalize the president’s conduct in carrying out the responsibilities of the executive branch under the Constitution.”

What that means for the case going forward remains to be seen. Trump’s lawyer conceded in the oral argument in April that at least some of the allegations in the indictment concern private conduct that would not be protected by any immunity defense. Likewise, the Justice Department lawyer arguing the case for special counsel Jack Smith said the prosecution could go ahead even if some official acts were protected.

At a minimum, there will be further proceedings before U.S. District Judge Tanya Chutkan to determine what, if any, of the other conduct alleged in the indictment is protected. Among the Trump conduct she will review to determine if they are official acts are his contacts with state election officials, private parties and members of the public.

The court’s three liberal justices dissented, with Justice Sonia Sotomayor writing that the ruling “makes a mockery of the principle, foundational to our Constitution and system of government that no man is above the law.”

Even if the new proceedings do not take much time, there is little chance for the trial to conclude before Election Day. It had previously been suggested that a trial would not start until at least three months after the Supreme Court ruling, which would mean it would potentially not start until early October at the earliest. The trial itself could last up to 12 weeks.

The case put the national spotlight on the court, which has a 6-3 conservative majority that includes three justices Trump appointed. The court handed Trump an election-year boost when it ruled in March that Colorado could not kick him off the ballot.

The justices were also criticized for their delay in taking up Trump’s appeal, which some view in itself as a victory for him as it meant the trial could not take place in March as originally planned.

Legally speaking, the case was unprecedented, as no president has ever been prosecuted after leaving office. Therefore, the court was wrestling with a legal question that had never come before it: whether a president has some form of immunity for his core duties derived from the constitutional principle of separation of powers, which delineates the powers of the presidency in relation to other branches of government.

The legal argument focused on Trump’s official acts, with both sides agreeing that a former president does not have immunity for personal conduct.

The Supreme Court intervened after a federal appeals court had ruled Feb. 6 that Trump was not immune from prosecution, saying that once he left office he became “citizen Trump” and should be treated like any other criminal defendant. The Justice Department has long maintained that a sitting president cannot be prosecuted.

The appeals court did not analyze which, if any, of the conduct in the indictment could be viewed as an official act, a fact that appeared to irk some of the justices during oral argument.

Trump’s lawyers pointed to a 1982 Supreme Court ruling that endorsed presidential immunity from civil lawsuits when the underlying conduct concerns actions within the “outer perimeter” of the president’s official responsibilities.

Smith’s team argued that there is no broad immunity that prevents former presidents from being prosecuted for criminal acts committed in office.

The federal indictment returned by a grand jury in Washington in August consisted of four counts: conspiracy to defraud the United States, conspiracy to obstruct an official proceeding, obstruction of and attempt to obstruct an official proceeding, and conspiracy against rights, specifically the right to vote.

In another Jan. 6-related case, the court on Friday narrowed the scope of law penalizing obstruction of an official proceeding. Trump also faces that charge but legal experts say the new ruling may not affect his case.

Trump, the indictment said, conspired to “overturn the legitimate results of the 2020 presidential election by using knowingly false claims of election fraud to obstruct the government function by which those results are collected, counted and certified.”

The indictment focuses on Trump’s involvement in a scheme to submit fake election certificates to Congress in the hope that they would nullify President Joe Biden’s victory. The chain of events culminated in the riot at the U.S. Capitol on Jan. 6.

Trump, who pleaded not guilty, says he was simply expressing his concerns, which were not based on any evidence, that the election was marred by widespread fraud. The case is one of four criminal prosecutions Trump is currently battling.

This article first appeared on NBCNews.com.

This article was originally published on TODAY.com